While House Democrats are moving ahead with a discharge petition for a “clean” continuing resolution, the timeline for the tactic makes it largely a moot point.

Democrats announced Oct. 4 that they would file a discharge petition on a GOP bill in order to swap the language and force the House to vote on a clean CR. But the discharge petition, which has worked only twice in recent history (on a 1986 gun rights bill and a 2002 campaign finance bill), is unlikely to break the logjam.

It looks like Democrats wouldn’t be able to bring the bill up for a vote until at least Oct. 28. That’s a week-and-a-half after what many believe is the more important deadline for Congress to meet: the Oct. 17 debt ceiling deadline when the Treasury says the government will be in danger of defaulting on its obligations.

That may be why many GOP centrists have rejected the call to sign a petition to bring up a policy-rider-free CR and instead have said they are more likely — though by no means certain — to use other procedural maneuvers if or when they decide to buck their leadership.

Here are the wonky details of how difficult it would be for Democrats to succeed:

The motion to discharge the bill (H Res 372) was introduced Oct. 4. Under clause 2(b)(1)(B) of rule XV, the bill is referred to the Rules Committee for seven legislative days before it is eligible for discharge petition signatures. Therefore, the first day it could receive signatures would be Oct. 12 (because the House did not hold a legislative day on Sunday).

If Democrats collected 218 signatures — which is a big if — the petition would then be placed on the Discharge Calendar.

Clause 2(d)(1) of rule XV provides that the motion to discharge is only privileged on the second and fourth Monday of a month, and only after it has been on the Discharge Calendar for seven legislative days.

Therefore, the next eligible day for Democrats to take the petition off the calendar would be Monday, Oct. 28.

And that’s assuming Republicans don’t take additional measures to block the discharge petition.

For instance, House Republicans could “recess” instead of adjourning, dragging legislative days on for multiple calendar days. Presumably, the Republicans who signed the discharge petition would join Democrats to vote on a daily motion to adjourn in that case, but it would be yet another hurdle in a discharge timeline that does not suggest success.

“It’s a cute procedural gimmick, but what Democrats need to do is come to conference and work out our differences,” a senior GOP aide told CQ Roll Call.

Of course, Democrats seem to think if they get 218 signatures, that would put pressure on Speaker John A. Boehner to put a clean CR up for a vote before the discharge petition ripens. But the matter is still left to the Ohio Republican, and judging by the way he has dug in on the CR, he doesn’t look likely to budge soon.

One scenario in which the discharge petition could matter is if Boehner and congressional leaders do not combine the CR and the debt limit. Many have assumed that Congress will try to reach a “grand bargain” on the debt limit and the CR before the Oct. 17 debt ceiling deadline.

But if Boehner doesn’t combine the issues, and if the shutdown stretches on for nearly a month, the dynamics in Congress, and indeed the economy, could be vastly different.